Integrated optics beam deflectors

ABSTRACT

This invention discloses an optical device including at least one first substrate defining a multiplicity of optical fiber positioning grooves, a multiplicity of optical fibers fixed in each of said multiplicity of optical fiber positioning grooves on the at least one first substrate, whereby the multiplicity of optical fibers lie in an optical fiber plane and the ends of each of the multiplicity of optical fibers lie substantially in a first predetermined arrangement in the optical fiber plane, a second substrate fixed onto the at least one first substrate such that an edge of the second substrate extends beyond the ends of each of the multiplicity of optical fibers, a lens assembly including a third substrate, and a lens fixed onto the third substrate, the lens assembly being mounted onto the second substrate such that the lens lies in a second predetermined arrangement with respect to the ends of each of the multiplicity of optical fibers, whereby the separation between the lens and the ends of each of the multiplicity of optical fibers is defined in a plane perpendicular to the optical fiber plane to a first degree of accuracy and the separation between the lens and the ends of each of the multiplicity of optical fibers is defined in the optical fiber plane to a second degree of accuracy, less than the first degree of accuracy. 
     A method for producing an optical device including at least one first substrate defining a multiplicity of optical fiber positioning grooves is also disclosed.

This application is a continuation of application Ser. No. 09/733,675filed on Dec. 8, 2000 now U.S. Pat. No. 6,377,733, which is a divisionalof application Ser. No. 09/350,024 filed on Jul. 9, 1999 now U.S. Pat.No. 6,366,720 claims the benefit thereof and incorporates the same byreference.

THE FIELD OF THE INVENTION

The present invention relates to integrated optical devices generallyand more particularly to packaging of integrated optical devices.

BACKGROUND OF THE INVENTION

Various types of integrated optical devices are known. It is well knownto pigtail an optical fiber onto an integrated optical device.Difficulties arise, however, when it is sought to pigtail multipleoptical fibers onto integrated optical devices. When the optical modesin waveguides and optical fibers are similar, it is conventional topigtail them by suitable alignment and butt coupling in an integratedoptical device.

When there exists a substantial disparity in the respective opticalmodes of the optical fibers and the waveguides, optical elements must beemployed to enable successful pigtailing. Particularly when the opticalmodes are relatively small, very high alignment accuracy is required inthe alignment of three elements, the waveguide, the optical element andthe fiber.

The following patents are believed to representative of the presentstate of the art: U.S. Pat. Nos. 5,737,138; 5,732,181; 5,732,173;5,721,797; 5,712,940; 5,712,937; 5,703,973; 5,703,980; 5,708,741;5,706,378; 5,611,014; 5,600,745; 5,600,741; 5,579,424; 5,570,442;5,559,915; 5,907,649; 5,898,806; 5,892,857; 5,881,190; 5,875,274;5,867,619; 5,859,945; 5,854,868; 5,854,867; 5,828,800; 5,793,914;5,784,509; 5,835,659; 5,656,120; 5,482,585; 5,482,585; 5,625,726;5,210,800; and 5,195,154.

SUMMARY OF THE INVENTION

The present invention seeks to provide a cost-effective and reliableintegrated optics packaging technique and optical devices constructedthereby.

There is thus provided in accordance with a preferred embodiment of thepresent invention an optical device including at least one firstsubstrate defining a multiplicity of optical fiber positioning grooves,a multiplicity of optical fibers fixed in each of the multiplicity ofoptical fiber positioning grooves on the at least one first substrate,whereby the multiplicity of optical fibers lie in an optical fiber planeand the ends of each of the multiplicity of optical fibers liesubstantially in a first predetermined arrangement in the optical fiberplane, a second substrate fixed onto the at least one first substratesuch that an edge of the second substrate extends beyond the ends ofeach of the multiplicity of optical fibers, a lens assembly including athird substrate, and a lens fixed onto the third substrate, the lensassembly being mounted onto the second substrate such that the lens liesin a second predetermined arrangement with respect to the ends of eachof the multiplicity of optical fibers, whereby the separation betweenthe lens and the ends of each of the multiplicity of optical fibers isdefined in a plane perpendicular to the optical fiber plane to a firstdegree of accuracy and the separation between the lens and the ends ofeach of the multiplicity of optical fibers is defined in the opticalfiber plane to a second degree of accuracy, less than the first degreeof accuracy.

Further in accordance with a preferred embodiment of the presentinvention the at least one first substrate comprises a pair of firstsubstrates having the optical fiber positioning grooves thereon arrangedin mutually facing relationship.

Still further in accordance with a preferred embodiment of the presentinvention the lens comprises a cylindrical lens which extends along acylindrical lens axis. Preferably the cylindrical lens axis liesparallel to the optical fiber plane.

Additionally in accordance with a preferred embodiment of the presentinvention the third substrate is fixed in engagement with the edge ofthe second substrate by an adhesive. Preferably the third substrate isfixed in engagement with the edge of the second substrate by anadhesive.

Additionally in accordance with a preferred embodiment of the presentinvention the multiplicity of optical fiber positioning grooves aremutually parallel. Preferably the multiplicity of optical fiberpositioning grooves are arranged in a fan arrangement in order tocompensate for optical aberrations.

There is also provided in accordance with a preferred embodiment of thepresent invention a method for producing an optical device including thesteps of forming a multiplicity of optical fiber positioning grooves onat least one first substrate, placing each of a multiplicity of opticalfibers in each of the multiplicity of optical fiber positioning grooveson the at least one first substrate, retaining each of the multiplicityof optical fibers in each of the multiplicity of optical fiberpositioning grooves on the at least one first substrate, such that themultiplicity of optical fibers lie in an optical fiber plane, preciselydefining the ends of each of the multiplicity of optical fibers so thatthey all lie substantially in a first predetermined arrangement, fixinga second substrate onto the at least one first substrate such that anedge of the second substrate extends beyond the ends of each of themultiplicity of optical fibers, fixing a lens onto a third substrate,precisely aligning the third substrate in engagement with the edge ofthe second substrate such that the lens lies in a second predeterminedarrangement with respect to the ends of each of the multiplicity ofoptical fibers, and fixing the third substrate in engagement with saidedge of the second substrate such that the lens lies in a secondpredetermined arrangement with respect to the ends of each of themultiplicity of optical fibers, whereby the separation between the lensand the ends of each of the multiplicity of optical fibers is defined ina plane perpendicular to the optical fiber plane to a first degree ofaccuracy and the separation between the lens and the ends of each of themultiplicity of optical fibers is defined in the optical fiber plane toa second degree of accuracy, less than the first degree of accuracy.Preferably the step of fixing the third substrate in engagement with theedge employs an adhesive and the step of precisely aligning the thirdsubstrate in engagement with the edge of the second substrate employs anexternal positioner.

Further in accordance with a preferred embodiment of the presentinvention the at least one first substrate includes a pair of firstsubstrates having the optical fiber positioning grooves thereon arrangedin mutually facing relationship.

Additionally or alternatively the lens includes a cylindrical lens whichextends along a cylindrical lens axis. Preferably the precisely aligningstep and the fixing step arrange the cylindrical lens such that thecylindrical lens axis lies parallel to the optical fiber plane.

Preferably the multiplicity of optical fiber positioning grooves aremutually parallel.

Alternatively accordance with a preferred embodiment of the presentinvention the multiplicity of optical fiber positioning grooves arearranged in a fan arrangement in order to compensate for opticalaberrations.

There is further provided in accordance with a preferred embodiment ofthe present invention an optical device including at least one opticalsubstrate having formed thereon at least one waveguide, at least onebase substrate onto which the at least one optical substrate is fixed,and at least one optical module, precisely positioned onto each at leastone base substrate and fixed thereto by means of side mounting blocksthereby to preserve precise mutual alignment of the at least one moduleand the at least one waveguide.

Further in accordance with a preferred embodiment of the presentinvention the at least one optical module includes a lens or includes acylindrical lens, and at least one optical fiber.

Preferably the at least one optical module also includes a lens which isoperative to couple light from the at least one fiber to the at leastone waveguide and also including the step of positioning output opticsincluding at least one output fiber on the at least one base substrateso as to receive light from the at least one waveguide. Additionally oralternatively the lens is operative to couple light from a first numberof fibers to a greater number of waveguides.

Additionally in accordance with a preferred embodiment of the presentinvention the at least one waveguide includes stacking a plurality ofbase substrates each having mounted thereon at least one opticalsubstrate having formed thereon at least one waveguide and wherein thestep of positioning the output optics includes arranging at least onelens to receive light from waveguides formed on multiple ones of theplurality of optical substrates. Preferably the step of positioning theoutput optics includes employing side mounting blocks thereby topreserve precise mutual alignment of said at least one lens and the atleast one waveguide.

Still further in accordance with a preferred embodiment of the presentinvention the step of positioning output optics includes employing sidemounting blocks thereby to preserve precise mutual alignment of said atleast one lens and said at least one waveguide, and the at least onewaveguide includes a multiplicity of waveguides. The step of positioningthe output optics includes positioning at least one lens so as toreceive light from multiple ones of the multiplicity of waveguides.

Still further in accordance with a preferred embodiment of the presentinvention the lens is operative to couple light from a first number offibers to an identical number of waveguides. Preferably the first numberof waveguides comprises at least one waveguide.

Still further in accordance with a preferred embodiment of the presentinvention the at least one optical substrate is a light deflector.

Additionally in accordance with a preferred embodiment of the presentinvention, the optical device includes output optics receiving lightfrom the at least one waveguide and including at least one output fiber.

Additionally or alternatively the output optics includes at least onelens fixed onto the base substrate by means of side mounting blocksthereby to preserve precise mutual alignment of the at least one lensand the at least one waveguide. The at least one optical substrate maybe a light deflector and preferably the at least one optical substrateis formed of gallium arsenide.

Still further in accordance with a preferred embodiment of the presentinvention the at least one waveguide includes a multiplicity ofwaveguides and wherein the output optics includes at least one lensreceiving light from multiple ones of the multiplicity of waveguides.Additionally or alternatively the output optics includes at least onelens receiving light from waveguides formed on multiple ones of theplurality of optical substrates. Furthermore the at least one opticalsubstrate may be a light deflector.

The output optics may also include at least one lens fixed onto the basesubstrate by means of side mounting blocks thereby to preserve precisemutual alignment of the at least one lens and the at least onewaveguide.

Additionally or preferably the at least one optical substrate is formedof gallium arsenide.

Still further in accordance with a preferred embodiment of the presentinvention the optical module includes at least one first substratedefining a multiplicity of optical fiber positioning grooves, amultiplicity of optical fibers fixed in each of the multiplicity ofoptical fiber positioning grooves on the at least one first substrate,whereby the multiplicity of optical fibers lie in an optical fiberplane. The ends of each of the multiplicity of optical fibers may liesubstantially in a first predetermined arrangement in the optical fiberplane. A second substrate is preferably fixed on at least one firstsubstrate such that an edge of the second substrate extends beyond theends of each of the multiplicity of optical fibers, a lens assemblyincluding a third substrate, and a lens fixed onto the third substrate,the lens assembly being mounted onto the second substrate such that thelens lies in a second predetermined arrangement with respect to the endsof each of the multiplicity of optical fibers. The separation betweenthe lens and the ends of each of the multiplicity of optical fibers maybe defined in a plane perpendicular to the optical fiber plane to afirst degree of accuracy and the separation between the lens and theends of each of the multiplicity of optical fibers may be defined in theoptical fiber plane to a second degree of accuracy, less than the firstdegree of accuracy.

Further in accordance with a preferred embodiment of the presentinvention the lens includes a cylindrical lens.

Additionally in accordance with a preferred embodiment of the presentinvention also including output optics receiving light from the at leastone waveguide and including at least one output fiber. Additionally oralternatively the output optics includes at least one lens fixed ontothe base substrate by means of side mounting blocks thereby to preserveprecise mutual alignment of the at least one lens and the at least onewaveguide. Preferably the at least one optical substrate is a lightdeflector and the at least one optical substrate is formed of galliumarsenide.

Further in accordance with a preferred embodiment of the presentinvention the at least one waveguide includes a multiplicity ofwaveguides and wherein the output optics includes at least one lensreceiving light from multiple ones of the multiplicity of waveguides.Additionally or alternatively the multiplicity of waveguides is formedon a plurality of optical substrates and the output optics includes atleast one lens receiving light from waveguides formed on multiple onesof the plurality of optical substrates.

Preferably the at least one optical substrate is a light deflector andthe output optics includes at least one lens fixed onto the basesubstrate by means of side mounting blocks thereby to preserve precisemutual alignment of the at least one lens and the at least onewaveguide. The at least one optical substrate may be formed of galliumarsenide.

There is also provided in accordance with a preferred embodiment of thepresent invention an optical device including at least one opticalsubstrate having formed thereon at least one waveguide having a centerwhich lies in a waveguide plane, a base substrate onto which the atleast one optical substrate is fixed and defining at least one opticalfiber positioning groove, and at least one optical fiber fixed in the atleast one optical fiber positioning groove on the base substrate,whereby a center of the at least one optical fiber lies in a plane whichis substantially coplanar with the waveguide plane.

Preferably electrical connections are mounted on the base substrate.

Additionally the at least one optical module is precisely positionedonto the base substrate and fixed thereto by means of side mountingblocks thereby to preserve precise mutual alignment of the at least onemodule and the at least one waveguide.

Additionally or alternatively the at least one optical substrate is alight deflector.

There is further provided in accordance with a preferred embodiment ofthe present invention a method for producing an optical device includingthe steps of forming at least one waveguide onto at least one opticalsubstrate, mounting the at least one optical substrate onto at least onebase substrate, and precisely positioning at least one optical moduleonto the base substrate, including employing side mounting blocksthereby to preserve precise mutual alignment of the at least one moduleand the at least one waveguide.

Additionally or alternatively the at least one optical module comprisesa lens which is preferably a cylindrical lens.

Further in accordance with a preferred embodiment of the presentinvention the at least one optical module includes at least one opticalfiber. Additionally or alternatively the at least one optical modulealso includes a lens which is operative to couple light from the atleast one fiber to the at least one waveguide. Preferably the lens isoperative to couple light from a first number of fibers to a greaternumber of waveguides.

Alternatively the lens is operative to couple light from a first numberof fibers to an identical number of waveguides.

Additionally in accordance with a preferred embodiment of the presentinvention the first number of waveguides includes at least onewaveguide.

Still further in accordance with a preferred the at least one opticalsubstrate is a light deflector.

Additionally in accordance with a preferred embodiment of the presentinvention, the method for producing an optical device also includes thesteps of providing output optics receiving light from the at least onewaveguide and including at least one output fiber. Furthermore, theoutput optics may include at least one lens fixed onto the basesubstrate by means of side mounting blocks thereby to preserve precisemutual alignment of the at least one lens and the at least onewaveguide. Additionally or alternatively the at least one opticalsubstrate is a light deflector. Preferably the at least one opticalsubstrate is formed of gallium arsenide.

Still further in accordance with a preferred embodiment of the presentinvention the at least one waveguide includes a multiplicity ofwaveguides and wherein the output optics includes at least one lensreceiving light from multiple ones of the multiplicity of waveguides.

Further in accordance with a preferred embodiment of the presentinvention the at least one waveguide includes a multiplicity ofwaveguides formed on a plurality of optical substrates and wherein theoutput optics includes at least one lens receiving light from waveguidesformed on multiple ones of the plurality of optical substrates.Additionally or alternatively the at least one optical substrate is alight deflector. Preferably the output optics includes at least one lensfixed onto the base substrate by means of side mounting blocks therebyto preserve precise mutual alignment of the at least one lens and the atleast one waveguide. Preferably the at least one optical substrate isformed of gallium arsenide.

Still further in accordance with a preferred embodiment of the presentinvention the optical module includes at least one first substratedefining a multiplicity of optical fiber positioning grooves, amultiplicity of optical fibers fixed in each of the multiplicity ofoptical fiber positioning grooves on the at least one first substrate,whereby the multiplicity of optical fibers lie in an optical fiber planeand the ends of each of the multiplicity of optical fibers liesubstantially in a first predetermined arrangement in the optical fiberplane, a second substrate fixed onto the at least one first substratesuch that an edge of the second substrate extends beyond the ends ofeach of the multiplicity of optical fibers, a lens assembly including athird substrate, and a lens fixed onto the third substrate, the lensassembly being mounted onto the second substrate such that the lens liesin a second predetermined arrangement with respect to the ends of eachof the multiplicity of optical fibers, whereby the separation betweenthe lens and the ends of each of the multiplicity of optical fibers isdefined in a plane perpendicular to the optical fiber plane to a firstdegree of accuracy and the separation between the lens and the ends ofeach of the multiplicity of optical fibers is defined in the opticalfiber plane to a second degree of accuracy, less than the first degreeof accuracy.

Additionally or alternatively the lens includes a cylindrical lens.Preferably the at least one optical substrate is a light deflector.

Additionally in accordance with a preferred embodiment of the presentinvention and also including providing output optics receiving lightfrom said at least one waveguide and including at least one outputfiber. Additionally or alternatively the output optics includes at leastone lens fixed onto the base substrate by means of side mounting blocksthereby to preserve precise mutual alignment of the at least one lensand the at least one waveguide. The at least one optical substrate maybe a light deflector and preferably the at least one optical substrateis formed of gallium arsenide.

Still further according to a preferred embodiment of the presentinvention the at least one waveguide includes a multiplicity ofwaveguides and wherein the output optics includes at least one lensreceiving light from multiple ones of the multiplicity of waveguides.

Further in accordance with a preferred embodiment of the presentinvention the at least one waveguide includes a multiplicity ofwaveguides formed on a plurality of optical substrates and wherein theoutput optics includes at least one lens receiving light from waveguidesformed on multiple ones of the plurality of optical substrates.Preferably the at least one optical substrate is a light deflector.

Additionally in accordance with a preferred embodiment of the presentinvention the output optics includes at least one lens fixed onto thebase substrate by means of side mounting blocks thereby to preserveprecise mutual alignment of the at least one lens and the at least onewaveguide. Preferably the at least one optical substrate is formed ofgallium arsenide.

There is also provided in accordance with yet another preferredembodiment of the present invention a method including forming on atleast one optical substrate at least one waveguide having a center whichlies in a waveguide plane, fixing the at least one optical substrateonto a base substrate and defining on the base substrate at least oneoptical fiber positioning groove, and fixing at least one optical fiberin the at least one optical fiber positioning groove on the basesubstrate, whereby a center of the at least one optical fiber lies in aplane which is substantially coplanar with the waveguide plane.

Preferably electrical connections are mounted on the base substrate.

Additionally the at least one optical module is precisely positionedonto the base substrate and fixed thereto by means of side mountingblocks thereby to preserve precise mutual alignment of the at least onemodule and the at least one waveguide.

Still further in accordance with a preferred embodiment of the presentinvention the at least one optical substrate is a light deflector.Preferably also including mounting electrical connections on said basesubstrate.

There is further provided in accordance with another preferredembodiment of the present invention a method for producing an opticaldevice including the steps of lithographically forming a multiplicity ofwaveguides onto an optical substrate, mounting the optical substrateonto a base substrate, and precisely positioning a fiber optic module,having a multiplicity of optical fiber ends and an optical modemodifying lens, onto the base substrate, including using at least oneexternal positioner, manipulating at least one of the fiber optic moduleand the base substrate relative to the other such that the mode of eachoptical fiber matches the mode of at least one corresponding waveguidewith relatively low light loss, and fixing the fiber optic module in adesired relative position on the base substrate independently of theexternal positioner, and disengaging the at least one externalpositioner from the modulated light source.

Further in accordance with a preferred embodiment of the presentinvention the step of fixing includes employing side mounting blocks tofix the module in position on the base substrate upon precise mutualalignment of the module and the multiplicity of waveguides.

Still further in accordance with a preferred embodiment of the presentinvention also including the step of producing a fiber optic modulewhich includes the steps of forming a multiplicity of optical fiberpositioning grooves on at least one first substrate, placing each of amultiplicity of optical fibers in each of the multiplicity of opticalfiber positioning grooves on the at least one first substrate, retainingeach of the multiplicity of optical fibers in each of the multiplicityof optical fiber positioning grooves on the at least one firstsubstrate, such that the multiplicity of optical fibers lie in anoptical fiber plane, precisely defining the ends of each of themultiplicity of optical fibers so that they all lie substantially in afirst predetermined arrangement, fixing a second substrate onto thefirst substrate such that an edge of the second substrate extends beyondthe ends of each of the multiplicity of optical fibers, fixing a lensonto a third substrate, precisely aligning the third substrate inengagement with the edge of the second substrate such that the lens liesin a second predetermined arrangement with respect to the ends of eachof the multiplicity of optical fibers, and fixing the third substrate inengagement with the edge of the second substrate such that the lenslies, in a second predetermined arrangement with respect to the ends ofeach of the multiplicity of optical fibers, whereby the separationbetween the lens and the ends of each of the multiplicity of opticalfibers is defined in a plane perpendicular to the optical fiber plane toa first degree of accuracy and the separation between the lens and theends of each of the multiplicity of optical fibers is defined in theoptical fiber plane to a second degree of accuracy, less than the firstdegree of accuracy.

Preferably the optical substrate is gallium arsenide and the opticaldevice functions as a switch.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be understood and appreciated more fully fromthe following detailed description, taken in conjunction with thedrawings in which:

FIGS. 1A-1I are simplified pictorial illustrations of a method forproducing an optical fiber module in accordance with a preferredembodiment of the present invention;

FIG. 2A-2C are simplified pictorial illustrations of three alternativeembodiments of a method for mounting an active integrated opticswaveguide assembly onto a base substrate which are useful in the presentinvention;

FIGS. 3A-3F are simplified pictorial illustrations of a method forproducing an optical device using an optical fiber module and anintegrated optics waveguide assembly in accordance with a preferredembodiment of the present invention corresponding to FIGS. 2A and 2B;

FIGS. 4A-4F are simplified pictorial illustrations of a method forproducing an optical device using an optical fiber module and anintegrated optics waveguide assembly in accordance with anotherpreferred embodiment of the present invention corresponding to theembodiment of FIG. 2C;

FIGS. 5A-5F are simplified pictorial illustrations of a method forproducing an optical device using an optical fiber module and anintegrated optics waveguide assembly in accordance with yet anotherpreferred embodiment of the present invention corresponding to theembodiment of FIG. 2C;

FIGS. 6A-6E are simplified pictorial illustrations of a method forassociating output optics with the optical device of FIG. 3F inaccordance with a preferred embodiment of the present invention;

FIGS. 7A-7D are simplified pictorial illustrations of a method forconstructing an integrated optics optical fiber switch using a pluralityof base substrates bearing integrated optics waveguide assemblies andoptical fiber modules as shown in FIG. 3F;

FIGS. 8A-8D are simplified pictorial illustrations of a method forassociating output optics with the optical device of FIG. 4F inaccordance with a preferred embodiment of the present invention;

FIGS. 9A-9D are simplified pictorial illustrations of a method forconstructing an integrated optics optical fiber switch using a pluralityof base substrates bearing integrated optics waveguide assemblies andoptical fiber modules as shown in FIG. 4F.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Reference is now made to FIGS. 1A-1I, which are simplified pictorialillustrations of a method for producing an optical fiber module inaccordance with a preferred embodiment of the present invention. Themethod preferably begins with the provision of a V-grooved substrate,such as substrate 10 in FIG. 1A or substrate 12 in FIG. 1B. Thesubstrate is typically silicon, but may alternatively be silica, glassor any other suitable material.

The V-grooves may be parallel as shown in FIG. 1A at reference numeral14 or non-parallel as shown in FIG. 1B at reference numeral 16. Thedescription that follows refers to a parallel orientation, it beingunderstood that a non-parallel orientation may be employed instead.

Preferably, the V-grooves are formed by lithography or by grinding. Theaccuracy of the dimensions of the V-grooves is preferably to a fractionof a micron, such that when optical fibers 20 are secured in theV-grooves 22 formed in a substrate 24, as shown in FIG. 1C, theirrelative alignment is within one-half micron in two dimensions.

Following placement of the optical fibers 20 in V-grooves 22, as shownin FIG. 1C, the fibers are secured in position by a cover element 26, asshown in FIG. 1D. The cover element 26 may be identical to the V-groovedsubstrate 24 in an upside down orientation.

It is appreciated that the ends of the optical fibers 20 may all besuitably aligned at the time of their placement in the V-grooves.Preferably, however, this alignment is not required and followingplacement of the fibers and securing thereof in the V-grooves 22, thefiber ends are cut and polished together with substrate 24 and coverelement 26 such that the fiber ends lie in the same plane as the edge ofthe substrate 24 and cover 26. In FIG. 1D, this plane is indicated byreference numeral 28.

Preferably, suitable adhesive is employed both at the stages shown inFIGS. 1C and 1D to retain the fibers in place and subsequently to holdthe cover element 26 onto substrate 24 in secure engagement with fibers20.

As seen in FIG. 1E, a sheet of glass 30 or any other suitable substrate,which is preferably transparent for ease of alignment, is aligned withcover element 26 such that at least one edge 32 thereof lies in highlyaccurate parallel alignment with plane 28, and separately therefrom by aprecisely determined distance. The substrate 30 is then fixed onto coverelement 26, as by means of a UV curable adhesive 27 and a UV lightsource 29, as shown in FIG. 1F.

Referring now to FIG. 1G, a lens 40, preferably a cylindrical lens,which is mounted onto a mounting substrate 42, is aligned with respectto edge 32 of substrate 30. This alignment is preferably provided to ahigh degree of accuracy, to the order of one-half micron, by means of avacuum engagement assembly 44 connected to a suitable positioner, notshown, such as Melees Grist Nanoblock. This degree of accuracy isgreater than that required in the parallelism and separation distancebetween edge 32 and plane 28. As seen in FIG. 1H, the substrate 42 isthen fixed onto edge 32 of substrate 30, as by means of a UV curableadhesive 41 and the UV light source 29.

FIG. 1I illustrates the resulting optical relationship between theoptical modes 50 of the fibers 20, which are seen to be circularupstream of lens 40 and the optical modes 52 downstream of the lens 40,which are seen to be highly elliptical. It is appreciated that it is aparticular advantage of the present invention that the highly ellipticalmodes which are produced by lens 40 are very similar to whose inintegrated optical waveguides, as is described in applicants publishedPCT application WO 98/59276. Furthermore, the arrangement describedhereinabove produces a mode from a single fiber which is sufficientlyhighly elliptical so that it may be coupled to a multiplicity ofwaveguides arranged side by side, as described in applicant's publishedPCT application WO 98/59276, the contents of which are herebyincorporated by reference. It is appreciated that in accordance with apreferred embodiment of the present invention, lens 40 may couple asingle fiber to a single waveguide or to multiple waveguides.

Reference is now made to FIGS. 2A-2C, which are simplified pictorialillustrations of three alternative embodiments of a method for mountingan active integrated optics waveguide assembly onto a base substratewhich is useful in the present invention.

FIG. 2A illustrates flip-chip type mounting of an integrated opticswaveguide device 100, such as a waveguide device described and claimedin applicant's published PCT application WO 98/59276, the disclosure ofwhich is hereby incorporated by reference. Device 100 is preferablyembodied in a flip-chip package, such as that described in FIG. 31 ofapplicant's published PCT application WO 98/59276. In this embodiment,device 100 is mounted onto an integrated electronic circuit 102, such asan ASIC.

FIG. 2B illustrates conventional wire bond type mounting of anintegrated optics waveguide device 104, such as a waveguide devicedescribed and claimed in applicant's published PCT application WO98/59276, the disclosure of which is hereby incorporated by reference.Device 104 is preferably embodied in a wire bond package, such as thatdescribed in FIG. 30 of applicant's published PCT application WO98/59276.

FIG. 2C illustrates conventional flip-chip type mounting of anintegrated optics waveguide device 100, such as a waveguide devicedescribed and claimed in applicant's published PCT application WO98/59276, the disclosure of which is hereby incorporated by reference.Device 100 is preferably embodied in a flip-chip package, such as thatdescribed in FIG. 31 of applicant's published PCT application WO98/59276.

The mountings of FIGS. 2A and 2B are both characterized in that thewaveguides of the active integrated optics waveguide device are locatedin a plane which is spaced from the surface of a substrate by a distanceof at least a few hundred microns. This may be contrasted from themounting of FIG. 2C, wherein the waveguides of the active integratedoptics waveguide device are located in a plane which is spaced from thesurface of a substrate by a distance of less than one hundred microns.

Reference is now made to FIGS. 3A-3F, which are simplified pictorialillustrations of a method for producing an optical device using anoptical fiber module and an integrated optics waveguide assembly inaccordance with a preferred embodiment of the present invention. Theillustrations of FIGS. 3A-3F show a mounting of the type illustrated inFIGS. 2A & 2B.

FIG. 3A shows a substrate 200 onto which is mounted an active integratedoptics waveguide device 202 as well as various other integrated circuits204. As seen in FIG. 3B, an optical fiber module 206, preferably of thetype described hereinabove with reference to FIGS. 1A-1I, is broughtinto proximity with substrate 200 and active integrated optics waveguidedevice 202, as by a vacuum engagement assembly 208, connected to asuitable positioner (not shown), such as Melles Griot Nanoblock.

As seen in FIG. 3C, the optical fiber module 206 is precisely positionedwith respect to the active integrated optics waveguide device 202 withsix degrees of freedom so as to achieve a high degree of accuracy inorder to realize optimal optical coupling efficiency between the fibersin module 206 and the waveguides in device 202. This degree of accuracyis greater than that required in the previously described alignmentsteps illustrated in FIGS. 1A-1I and preferably reaches one tenth of amicron.

FIG. 3D illustrates precise mounting of the optical fiber module 206with respect to the active integrated optics waveguide device 202 onsubstrate 200. This precise mounting is preferably achieved by using thepositioner (not shown) to manipulate the fiber optic module 206 relativeto substrate 200 such that the mode of each optical fiber 209 in module206 matches the mode of at least one corresponding waveguide ofwaveguide device 202 with relatively low light loss.

The fiber optic module 206 is mounted in a desired relative position onthe substrate 200 independently of the positioner by employing sidemounting blocks 210 to fix the module 206 in position on substrate 200upon precise mutual alignment of the module 206 and the waveguide device202.

Preferably side mounting blocks 210 are carefully positioned alongsidemodule 206 and are bonded thereto and to substrate 200, preferably usinga thin layer of UV curable adhesive 211 which does not involvesignificant shrinkage during curing, as by use of a UV light source 220as shown in FIG. 3E, so that the relative position shown in FIG. 3D ispreserved, as seen in FIG. 3F. It is appreciated that in order to affixthe mounting blocks 210 to the substrate 200, a coating of the adhesive211 is applied to the appropriate side surfaces and lower surfaces ofthe mounting blocks 210.

The use of side mounting blocks 210 enables accurate fixation with sixdegrees of freedom by virtue of the use of the thin layer of adhesive211, which does not involve significant shrinkage during curing, alongtwo mutually orthogonal planes.

Reference is now made to FIGS. 4A-4F, which are simplified pictorialillustrations of a method for producing an optical device using anoptical fiber module and an integrated optics waveguide assembly inaccordance with another preferred embodiment of the present inventioncorresponding to the embodiment of FIG. 2C.

As noted above, in the mounting arrangement of FIG. 2C, the waveguidesof the active integrated optics waveguide device are located in a planewhich is spaced from the surface of a substrate by a distance of lessthan one hundred microns. In order to accommodate this very smallspacing a hole or a recess is formed in the substrate to receive theoptical fiber module.

FIG. 4A shows a substrate 300 onto which is mounted an active integratedoptics waveguide device 302 as well as various other integrated circuits304. A hole or recess 305 is preferably formed in substrate 300 asshown. As seen in FIG. 4B, an optical fiber module 306, preferably ofthe type described hereinabove with reference to FIGS. 1A-1I, is broughtinto proximity with substrate 300 and active integrated optics waveguidedevice 302, as by a vacuum engagement assembly 308, connected to asuitable positioner (not shown), such as Melles Griot Nanoblock.

As seen in FIG. 4C, the optical fiber module 306 is precisely positionedwith respect to the active integrated optics waveguide device 302 withsix degrees of freedom so as to achieve a high degree of accuracy inorder to realize optimal optical coupling efficiency between the fibersin module 306 and the waveguides in device 302. This degree of accuracyis greater than that required in the previously described alignmentsteps illustrated in FIGS. 1A-1I and preferably reaches one tenth of amicron.

FIG. 4D illustrates precise mounting of the optical fiber module 306with respect to the active integrated optics waveguide device 302 onsubstrate 300 partially overlapping hole 305, such that the cylindricallens, such as lens 40 (FIG. 1H) and the ends of the optical fibers, suchas fibers 20 (FIG. 1D) lie partially below the top surface of substrate300. This construction ensures that the images of the centers of theends of fibers 20 lie in the same plane as the centers of the waveguidesof waveguide device 302. This precise mounting is preferably achieved byusing the positioner (not shown) to manipulate the fiber optic module306 relative to substrate 300 such that the mode of each optical fiber20 in module 306 matches the mode of at least one correspondingwaveguide of waveguide device 302 with relatively low light loss.

The fiber optic module 306 is mounted in a desired relative position onthe substrate 302 independently of the positioner by employing sidemounting blocks 310 to fix the module 306 in position on substrate 300upon precise mutual alignment of the module 306 and the waveguide device302.

Preferably side mounting blocks 310 are carefully positioned alongsidemodule 306 and are bonded thereto and to substrate 300, preferably usinga thin layer of UV curable adhesive 311 which does not involvesignificant shrinkage during curing, as by use of a UV light source 320as shown in FIG. 4E, so that the relative position shown in FIG. 4D ispreserved, as seen in FIG. 4F.

The use of side mounting blocks 310 enables accurate fixation with sixdegrees of freedom by virtue of the use of the thin layer of adhesive311, which does not involve significant shrinkage during curing, alongtwo mutually orthogonal planes.

Reference is now made to FIGS. 5A-5F, which are simplified pictorialillustrations yet another method for producing an optical device usingan optical fiber module and an integrated optics waveguide assembly inaccordance with yet another preferred embodiment of the presentinvention corresponding to the embodiment of FIG. 2C.

FIG. 5A shows a substrate 400 onto which is mounted an active integratedoptics waveguide device 402 as well as various other integrated circuits404. A hole or recess 405 is preferably formed in substrate 400 asshown.

In this embodiment a multiplicity of optical fibers 406 are mounted inV-grooves 407 formed in substrate 400, such that the centers of the endsof fibers 406 all lie in the same plane as that of the centers of thewaveguides of waveguide device 402. It is appreciated that this type ofstructure may be adapted for use with the embodiment of FIGS. 2A and 2Bby providing a raised platform portion of substrate 400 underlyingV-grooves 407. In such an arrangement, the centers of the ends of fibers406 would all lie in the same plane as that of the centers of thewaveguides of waveguide device 100 (FIG. 2A) or 104 (FIG. 2B).

As seen in FIG. 5B, a lens module 408, preferably comprising a lens 409fixedly mounted onto a mounting substrate 410, is brought into proximitywith substrate 400 and active integrated optics waveguide device 402, asby a vacuum engagement assembly 411, connected to a suitable positioner(not shown), such as Melles Griot Nanoblock.

As seen in FIG. 5C, the lens module 408 is precisely positioned withrespect to the active integrated optics waveguide device 402 with sixdegrees of freedom so as to achieve a high degree of accuracy in orderto realize optimal optical coupling efficiency between the fibers 406and the waveguides in device 402. This degree of accuracy is greaterthan that required in the previously described alignment stepsillustrated in FIGS. 1A-1I and preferably reaches one tenth of a micron.

FIG. 5D illustrates precise mounting of the lens module 408 with respectto the active integrated optics waveguide device 402 on substrate 400partially overlapping hole 405, such that the lens 409 lies partiallybelow the top surface of substrate 400. This construction ensures thatthe images of the centers of the ends of fibers 406 lie in the sameplane as the centers of the waveguides of waveguide device 402. Thisprecise mounting is preferably achieved by using the positioner (notshown) to manipulate the lens module 408 relative to substrate 400 suchthat the mode of each optical fiber 406 matches the mode of at least onecorresponding waveguide of waveguide device 402 with relatively lowlight loss.

The lens module 408 is mounted in a desired relative position on thesubstrate 400 independently of the positioner by employing side mountingblocks 412 to fix the module 408 in position on substrate 400 uponprecise mutual alignment of the module 408 and the waveguide device 402.

Preferably side mounting blocks 412 are carefully positioned alongsidemodule 408 and are bonded thereto and to substrate 400, preferably usinga thin layer of UV curable adhesive 413 which does not involvesignificant shrinkage during curing, as by use of a UV light source 420as shown in FIG. 5E, so that the relative position shown in FIG. 5D ispreserved, as seen in FIG. 5F.

The use of side mounting blocks 412 enables accurate fixation with sixdegrees of freedom by virtue of the use of the thin layer of adhesive413, which does not involve significant shrinkage during curing, alongtwo mutually orthogonal planes.

Reference is now made to FIGS. 6A-6E, which are simplified pictorialillustrations of a method for associating output optics with the opticaldevice of FIG. 3F in accordance with a preferred embodiment of thepresent invention;

FIG. 6A shows a chassis 500 onto which is mounted an optical device 501,preferably the optical device described hereinabove and shown in FIG.3F. For the sake of conciseness and clarity, the reference numeralsappearing in FIG. 3F are employed also in FIG. 6A as appropriate. Alsomounted on chassis 500 is an optical fiber bundle 502 and a lens 504arranged such that the center of the lens 504 lies in the same plane asthe centers of the ends of the fibers in fiber bundle 502 withinconventional mechanical tolerances, such as 10-50 microns.

As seen in FIG. 6A, a lens module 508, preferably comprising a lens 509fixedly mounted onto a mounting substrate 510, is brought into proximitywith substrate 200 of device 501 and active integrated optics waveguidedevice 202 of device 501, as by a vacuum engagement assembly 511,connected to a suitable positioner (not shown), such as Melles GriotNanoblock.

As seen in FIG. 6B, the lens module 508 is precisely positioned withrespect to the active integrated optics waveguide device 202 with sixdegrees of freedom so as to achieve a high degree of accuracy in orderto realize optimal optical coupling efficiency between the fibers offiber bundle 502 and the waveguides in device 202. This degree ofaccuracy is greater than that required in the previously describedalignment steps illustrated in FIGS. 1A-1I and preferably reaches onetenth of a micron.

FIG. 6C illustrates precise mounting of the lens module 508 with respectto the active integrated optics waveguide device 202 of device 501. Thisconstruction ensures that the images of the centers of the ends offibers of fiber bundle 502 lie in the same plane as the centers of thewaveguides of waveguide device 202. This precise mounting is preferablyachieved by using the positioner (not shown) to manipulate the lensmodule 508 relative to substrate 200 such that the mode of each opticalfiber in bundle 502 matches the mode of at least one correspondingwaveguide of waveguide device 202 with relatively low light loss.

The lens module 508 is mounted in a desired relative position on thesubstrate 200 independently of the positioner by employing side mountingblocks 512 to fix the module 508 in position on substrate 200 uponprecise mutual alignment of the module 508 and the waveguide device 202.

Preferably side mounting blocks 512 are carefully positioned alongsidemodule 508 and are bonded thereto and to substrate 200, preferably usinga thin layer of UV curable adhesive 513 which does not involvesignificant shrinkage during curing, as by use of a UV light source 520as shown in FIG. 6D, so that the relative position shown in FIG. 6C ispreserved, as seen in FIG. 6E.

The use of side mounting blocks 512 enables accurate fixation with sixdegrees of freedom by virtue of the use of the thin layer of adhesive513, which does not involve significant shrinkage during curing, alongtwo mutually orthogonal planes.

Reference is now made to FIGS. 7A-7D, which are simplified pictorialillustrations of a method for constructing an integrated optics opticalfiber switch using a plurality of base substrates bearing integratedoptics waveguide assemblies and optical fiber modules as shown in FIG.3F.

The switch is constructed on the basis of the apparatus shown in FIG.6E. For the sake of conciseness and clarity, the reference numeralsappearing in FIG. 6E are also employed, as appropriate in FIGS. 7A-7D.As seen in FIG. 7A an optical device 601, preferably identical tooptical device 501 (FIG. 6E), as shown in FIG. 3F, is stacked overoptical device 501 and spaced therefrom by mounting spacers 602. For thesake of conciseness and clarity, the reference numerals appearing inFIG. 3F are also employed, as appropriate in FIGS. 7A-7D. Spacers 602may be mounted either on device 501 as shown or alternatively on device601 or on chassis 500.

The alignment between devices 501 and 601 may be within conventionalmechanical tolerances, such as 10 microns. The most important aspect ofthe alignment between devices 501 and 601 is the parallelism of theplanes of the respective substrates 200 of devices 501 and 601 about theaxes of the waveguides of respective optical devices 202.

As seen in FIG. 7B, a lens module 608, preferably comprising a lens 609fixedly mounted onto a mounting substrate 610, is brought into proximitywith substrate 200 of device 601 and active integrated optics waveguidedevice 202 of device 601, as by a vacuum engagement assembly 611,connected to a suitable positioner (not shown), such as Melles GriotNanoblock.

As seen in FIG. 7C, the lens module 608 is precisely positioned withrespect to the active integrated optics waveguide device 202 of device601 with six degrees of freedom so as to achieve a high degree ofaccuracy in order to realize optimal optical coupling efficiency betweenthe fibers of fiber bundle 502 and the waveguides in device 202 ofdevice 601. This degree of accuracy is greater than that required in thepreviously described alignment steps illustrated in FIGS. 1A-1I andpreferably reaches one tenth of a micron.

Precise mounting of the lens module 608 with respect to the activeintegrated optics waveguide device 202 of device 601 as describedhereinabove with respect to device 501 ensures that the images of thecenters of the ends of fibers of fiber bundle 502 lie in the same planeas the centers of the waveguides of waveguide device 202 of device 601.This precise mounting is preferably achieved by using the positioner(not shown) to manipulate the lens module 608 relative to substrate 200of device 601 such that the mode of each optical fiber in bundle 502matches the mode of at least one corresponding waveguide of waveguidedevice 202 of device 601 with relatively low light loss.

As seen in FIG. 7D, the lens module 608 is mounted in a desired relativeposition on the substrate 200 of device 601 independently of thepositioner by employing side mounting blocks 612 to fix the module 608in position on substrate 200 of device 601 upon precise mutual alignmentof the module 608 and the waveguide device 202 of device 601.

Preferably side mounting blocks 612 are carefully positioned alongsidemodule 608 and are bonded thereto and to substrate 200 of device 601,preferably using a thin layer of UV curable adhesive 613 which does notinvolve significant shrinkage during curing, as by use of a UV lightsource (not shown).

Reference is now made to FIGS. 8A-8D, which are simplified pictorialillustrations of a method for associating output optics with the opticaldevice of FIG. 4F in accordance with a preferred embodiment of thepresent invention;

FIG. 8A shows a chassis 700 onto which is mounted an optical device 701,preferably the optical device described hereinabove and shown in FIG.4F. For the sake of conciseness and clarity, the reference numeralsappearing in FIG. 4F are employed also in FIG. 8A as appropriate. Alsomounted on chassis 700 is an optical fiber bundle 702 and a lens 704arranged such that the center of the lens 704 lies in the same plane asthe centers of the ends of the fibers in fiber bundle 702 withinconventional mechanical tolerances, such as 10-50 microns.

As seen in FIG. 8A, a lens module 708, preferably comprising a lens 709fixedly mounted onto a mounting substrate 710, is brought into proximitywith substrate 300 of device 701 and active integrated optics waveguidedevice 302 of device 701, as by a vacuum engagement assembly 711,connected to a suitable positioner (not shown), such as Melles GriotNanoblock. As seen in FIG. 8B, the lens module 708 is preciselypositioned with respect to the active integrated optics waveguide device302 with six degrees of freedom so as to achieve a high degree ofaccuracy in order to realize optimal optical coupling efficiency betweenthe fibers of fiber bundle 702 and the waveguides in device 302. Thisdegree of accuracy is greater than that required in the previouslydescribed alignment steps illustrated in FIGS. 1A-1I and preferablyreaches one tenth of a micron.

FIG. 8C illustrates precise mounting of the lens module 708 with respectto the active integrated optics waveguide device 302 of device 701. Thisconstruction ensures that the images of the centers of the ends offibers of fiber bundle 702 lie in the same plane as the centers of thewaveguides of waveguide device 302. This precise mounting is preferablyachieved by using the positioner (not shown) to manipulate the lensmodule 708 relative to substrate 300 such that the mode of each opticalfiber in bundle 702 matches the mode of at least one correspondingwaveguide of waveguide device 302 with relatively low light loss.

The lens module 708 is mounted in a desired relative position on thesubstrate 300 independently of the positioner by employing side mountingblocks 712 to fix the module 708 in position on substrate 300 uponprecise mutual alignment of the module 708 and the waveguide device 302.

Preferably side mounting blocks 712 are carefully positioned alongsidemodule 708 and are bonded thereto and to substrate 300, preferably usinga thin layer of UV curable adhesive 713 which does not involvesignificant shrinkage during curing, as by use of a UV light source 720as shown in FIG. 8C, so that the relative position shown in FIG. 8C ispreserved, as seen in FIG. 8D.

The use of side mounting blocks 712 enables accurate fixation with sixdegrees of freedom by virtue of the use of the thin layer of adhesive713, which does not involve significant shrinkage during curing, alongtwo mutually orthogonal planes.

Reference is now made to FIGS. 9A-9D, which are simplified pictorialillustrations of a method for constructing an integrated optics opticalfiber switch using a plurality of base substrates bearing integratedoptics waveguide assemblies and optical fiber modules as shown in FIG.4F.

The switch is constructed on the basis of the apparatus shown in FIG.8D. For the sake of conciseness and clarity, the reference numeralsappearing in FIG. 8D are also employed, as appropriate in FIGS. 9A-9D.As seen in FIG. 9A an optical device 801, preferably identical tooptical device 701 (FIG. 8D), as shown in FIG. 4F, is stacked overoptical device 701 and spaced therefrom by mounting spacers 802. For thesake of conciseness and clarity, the reference numerals appearing inFIG. 4F are also employed, as appropriate in FIGS. 9A-9D. Spacers 802may be may mounted either on device 701 as shown or alternatively ondevice 801 or on chassis 700.

The alignment between devices 701 and 801 may be within conventionalmechanical tolerances, such as 10 microns. The most important aspect ofthe alignment between devices 701 and 801 is the parallelism of theplanes of the respective substrates 300 of devices 701 and 801 about theaxes of the waveguides of respective optical devices 302 (FIG. 9B).

As seen in FIG. 9C, a lens module 808, preferably comprising a lens 809fixedly mounted onto a mounting substrate 810, is brought into proximitywith substrate 300 of device 801 and active integrated optics waveguidedevice 302 of device 801, as by a vacuum engagement assembly 811,connected to a suitable positioner (not shown), such as Melles GriotNanoblock.

Also seen in FIG. 9C, the lens module 808 is precisely positioned withrespect to the active integrated optics waveguide device 302 of device801 with six degrees of freedom so as to achieve a high degree ofaccuracy in order to realize optimal optical coupling efficiency betweenthe fibers of fiber bundle 702 and the waveguides in device 302 ofdevice 801. This degree of accuracy is greater than that required in thepreviously described alignment steps illustrated in FIGS. 1A-1I andpreferably reaches one tenth of a micron.

Precise mounting of the lens module 808 with respect to the activeintegrated optics waveguide device 302 of device 801 as describedhereinabove with respect to device 701 ensures that the images of thecenters of the ends of fibers of fiber bundle 702 lie in the same planeas the centers of the waveguides of waveguide device 302 of device 801.This precise mounting is preferably achieved by using the positioner(not shown) to manipulate the lens module 808 relative to substrate 300of device 801 such that the mode of each optical fiber in bundle 702matches the mode of at least one corresponding waveguide of waveguidedevice 302 of device 801 with relatively low light loss.

As seen in FIG. 9D, the lens module 808 is mounted in a desired relativeposition on the substrate 300 of device 801 independently of thepositioner by employing side mounting blocks 812 to fix the module 808in position on substrate 300 of device 801 upon precise mutual alignmentof the module 808 and the waveguide device 302 of device 801.

Preferably side mounting blocks 812 are carefully positioned alongsidemodule 808 and are bonded thereto and to substrate 300 of device 801,preferably using a thin layer of UV curable adhesive 813 which does notinvolve significant shrinkage during curing, as by use of a UV lightsource 820.

It will be appreciated by persons skilled in the art that the presentinvention is not limited by the claims which follow, rather the scope ofthe invention includes both combinations and subcombinations of thevarious features described hereinabove as well as variations andmodifications thereof which would occur to a person of ordinary skill inthe art upon reading the foregoing description and which are not in theprior art. 3857

What is claimed is:
 1. An optical device comprising: at least oneoptical substrate having formed thereon at least one waveguide having acenter which lies in a waveguide plane; a base substrate onto which saidat least one optical substrate is fixed and defining at least oneoptical fiber positioning groove; and at least one optical fiber fixedin said at least one optical fiber positioning groove on said basesubstrate, whereby a center of said at least one optical fiber lies in aplane which is substantially coplanar with said waveguide plane.
 2. Anoptical device according to claim 1 and also comprising electricalconnections mounted on said base substrate.
 3. An optical deviceaccording to claim 1 and also comprising at least one optical module,precisely positioned onto said base substrate and fixed thereto by meansof side mounting blocks thereby to preserve precise mutual alignment ofsaid at least one module and said at least one waveguide.
 4. An opticaldevice according to claim 3 and wherein said at least one opticalsubstrate is a light deflector.
 5. An optical device according to claim4 and also comprising electrical connections mounted on said basesubstrate.